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Re: iPhone and Network Disruptions ...


From: Adrian Chadd <adrian () creative net au>
Date: Thu, 26 Jul 2007 18:01:02 +0800


On Wed, Jul 25, 2007, Warren Kumari wrote:

You have a couple of switches with STP turned off -- someone plugs in  
some random cable, forming a bridge loop....... and everything  
continues running fine, until some time in the future when it all  
goes to hell in a hand-basket. Now, I could understand the system  
remaining stable until the first  broadcast / unknown MAC caused  
flooding to happen, but I have seen this system remain stable for  
anywhere from a few days to in a few weeks before suddenly exploding.

If you want to hear about something whacked along those lines - imagine
two access points which had spanning tree disabled, connected to
a pair of switches on a vlan which wasn't running stp (thanks to
platform stp limitations, the switches running pvstp and said
campus having >800 vlans), and said ap's would occasionally associate
in infrastructure mode - which would cause a broadcast storm
on that vlan and fill trunk pipes with spaf. Debugging that one was
hilarious.

Hum.





Adrian


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